Prospective Clinical Evaluation of Customized Titanium Occlusive Barriers with Window Modification for Guided Bone Regeneration: Radiographic and Histological Outcomes

This study aimed to quantify horizontal and vertical bone gain using superimposition of preoperative and postoperative cone beam computed tomography (CBCT) in severe alveolar ridge defects treated with a modified guided bone regeneration (GBR) technique based on customized titanium occlusive barriers with a window design, combined with autologous blood clot and β-tricalcium phosphate (β-TCP). In this prospective case series, 13 patients (28 defects) were treated. Customized titanium barriers were digitally designed based on CBCT data and manufactured by laser sintering. The barriers were fixed over the defects and filled with a mixture of an autologous blood clot and β-TCP, providing an osteoconductive scaffold within a stable regenerative compartment. A standardized window-based follow-up protocol was applied during healing, including irrigation and controlled deepithelialization. Primary outcomes were horizontal and vertical bone gain, assessed by pre- and postoperative CBCT superimposition. Histological evaluation was performed at the time of implant placement. After 8 months, significant bone gain was observed, with a mean horizontal gain of 4.50 ± 2.02 mm and a mean vertical gain of 4.40 ± 2.82 mm (<i>p</i> < 0.0001), confirmed by linear mixed-effects models and patient-level sensitivity analyses (<i>p</i> < 0.001). Histological analysis revealed well-vascularized newly formed bone with active osteoblasts and no inflammatory response. Keratinized gingiva formation was observed at all sites. One minor complication (mild screw loosening) was recorded and successfully resolved. This study is presented as a prospective case series; therefore, the results should be interpreted as exploratory evidence and do not allow direct comparisons or conclusions regarding equivalence or superiority over other GBR techniques. The present report specifically evaluates the regenerative phase prior to functional loading; therefore, although implants were placed according to protocol, implant survival and long-term functional outcomes were not assessed and cannot be inferred from these data. Within the limitations of this prospective case series, customized titanium occlusive barriers with a window design demonstrated promising results for horizontal and vertical bone augmentation and keratinized gingiva formation, without the need for autologous bone grafts or primary wound closure.